bpo-39245: Switch to public API for Vectorcall (GH-18460)

The bulk of this patch was generated automatically with:

    for name in \
        PyObject_Vectorcall \
        Py_TPFLAGS_HAVE_VECTORCALL \
        PyObject_VectorcallMethod \
        PyVectorcall_Function \
        PyObject_CallOneArg \
        PyObject_CallMethodNoArgs \
        PyObject_CallMethodOneArg \
    ;
    do
        echo $name
        git grep -lwz _$name | xargs -0 sed -i "s/\b_$name\b/$name/g"
    done

    old=_PyObject_FastCallDict
    new=PyObject_VectorcallDict
    git grep -lwz $old | xargs -0 sed -i "s/\b$old\b/$new/g"

and then cleaned up:

- Revert changes to in docs & news
- Revert changes to backcompat defines in headers
- Nudge misaligned comments

1 files changed, 1 insertions, 1 deletions

diff --git a/Modules/pyexpat.c b/Modules/pyexpat.c
index 9016734..a7f8b50 100644
--- a/Modules/pyexpat.c
+++ b/Modules/pyexpat.c
@@ -119,7 +119,7 @@ set_error(xmlparseobject *self, enum XML_Error code)
                                   XML_ErrorString(code), lineno, column);
     if (buffer == NULL)
         return NULL;
-    err = _PyObject_CallOneArg(ErrorObject, buffer);
+    err = PyObject_CallOneArg(ErrorObject, buffer);
     Py_DECREF(buffer);
     if (  err != NULL
           && set_error_attr(err, "code", code)